Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond the annotations (readOnlyHint=false, destructiveHint=true, openWorldHint=true), the description discloses the blocking/waiting semantics, the artifact and pendingApproval return shapes, and the concrete 15-minute timeout behavior with running:true plus the follow-up path via ranla_get_thread. That timeout and follow-up contract is not derivable from annotations and is exactly what an agent needs to handle a long turn.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Four sentences, front-loaded with the action, then usage, then return shape, then the timeout edge case. Every sentence carries distinct information and nothing is repeated.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a mutating, open-world tool with annotations and an output schema, the description covers when to use it, what it returns, and the async timeout path. The only gap is that it does not state that omitting threadId starts a new thread, leaving the optional-parameter behavior to inference.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so text and threadId are already documented in the schema (including the pointer to ranla_open_thread). The description adds no parameter-level detail and never mentions threadId or what happens when it is omitted, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb+resource ('Send a message to Ranla and wait for the turn') and scopes the tool via 'strategy and anything that changes the account.' It implicitly separates itself from ranla_command but never names that sibling, so an agent must infer the boundary.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

'Use for strategy and anything that changes the account' gives clear positive selection criteria, and the closing sentence routes the agent to ranla_get_thread for late answers. There is no explicit 'do not use when...' statement or named alternative for simpler operations, so the boundary with ranla_command is left implicit.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.